The present invention relates to a gas-insulated switchgear device for high- and medium-voltage applications, i.e. for voltages greater than 1000 Volt, having improved functions and characteristics. In particular, the device according to the invention, by virtue of its innovative structure, allows to optimize execution of the required electric switching, according to a solution which is at the same time simple, effective and compact.
It is known from the art that electric switching operations, for both interruption and disconnection, in gas-insulated circuit breaker and disconnector units are provided by virtue of the translatory motion of one or more moving contacts which can couple/uncouple with respect to corresponding fixed contacts. A significant drawback of known types of devices is the fact that the various switching operations, for example for disconnection on the input line or on the output line, are performed by means of dedicated components which are structurally separate and mutually distinct; in this way, the number of components used to implement the various switching operations is large and entails an increase in the space occupation and total volume of the device, with a consequent cost increase.
Furthermore, the necessary switching operations are performed by using actuation devices which comprise actuators of the mechanical or hydraulic type which are mechanically connected to a moving contact to be moved by virtue of appropriate operating elements.
The actuation devices of the known art generally require complicated kinematic systems to transmit motion to the moving contact. In particular, the switching operation for disconnection requires the coordinated movement of one or more moving contacts, so that the opening/closure of the disconnection contacts occurs in the intended sequence. This usually entails complicated coupling mechanisms and/or complicated actuation and control systems, especially when disconnection occurs on multiple-bar systems.
In view of the mechanical complexity of the movement elements, maintenance interventions are necessary in order to maintain nominal behavior and therefore ensure repeatability of the movement, compensating for the variations caused by wear and aging of the system.
The aim of the present invention is to provide a gas-insulated switchgear device in which the electrical switching operations, particularly for disconnection, occur in a simple and easily controllable way.
Within the scope of this aim, an object of the present invention is to provide a gas-insulated switchgear device which has reduced mechanical complexity and a simplified structure with respect to the devices of the known art.
Another object of the present invention is to provide a gas-insulated switchgear device in which the switching operation for disconnection occurs by using and moving a reduced number of mechanical parts.
Another object of the present invention is to provide a gas-insulated switchgear device which has reduced dimensions and space occupation.
Another object of the present invention is to provide a gas-insulated switchgear device which is highly reliable, relatively easy to provide and at competitive costs.
This aim, these objects and others which will become apparent hereinafter are achieved by a gas-insulated switchgear device, having a first bushing which accommodates a first terminal and a second bushing which accommodates a second terminal, a first enclosure which contains an interruption unit, characterized in that it comprises at least one first disconnection unit which has a first fixed contact which is electrically connected to said interruption unit and a second fixed contact at ground voltage, a first moving contact which is electrically connected to the first terminal and can be coupled to said first and second fixed contacts, said moving contact being fixed to a rotary operating element and rotating rigidly therewith, and in that the fixed contacts that can be coupled to said first moving contact lie on the rotation plane of said moving contact.
The device according to the invention can be of the segregated-phase or joined-phase type, for a single-bar or multiple-bar system, with single-pole or three-pole actuation.
In the device according to the invention, the disconnection maneuver therefore occurs by rotation of the moving contact about a rotation axis. By virtue of the rotation, the moving contact, which in practice constitutes a rotating extension of the first terminal, couples/uncouples with respect to one of the two corresponding fixed contacts, performing the switching for disconnection and grounding of the first terminal, or maintaining electrical continuity. The moving contact can furthermore assume an intermediate position for simply disconnecting the first terminal without grounding it. For these purposes, the moving contact and the fixed contacts are arranged in such a mutual position that the ends of the fixed contacts that must engage the end of the moving contact lie on the rotation plane traced by said end of the moving contact. For the sake of simplicity, when reference is made in the present invention to the relative position of the fixed contacts and of the moving contact, reference is always intended to the relative position of the ends of the fixed contacts and of the moving contact that can be coupled thereto.
By appropriately dimensioning the position of the fixed contacts and of the moving contact it is possible to minimize the volume and the space required by the disconnection unit and therefore by the entire device, maintaining easy execution of switching for disconnection.
Another advantage of the device according to the invention is the fact that it constitutes, in practice, a prefabricated module which can be easily transported to the installation site.